An inkjet head that ejects ink from nozzles has been known as a liquid ejection device. For example, the known inkjet head includes a pressure chamber substrate having pressure chambers communicating with nozzles. The pressure chamber substrate includes piezoelectric elements provided corresponding to the pressure chambers.
The pressure chambers are aligned in four rows in the pressure chamber substrate. The piezoelectric elements are also aligned in four rows in accordance with the arrangement pattern of the pressure chambers. Leads extend from the respective piezoelectric elements in a direction orthogonal to a direction in which the piezoelectric elements are aligned, i.e., the leads extend outwardly with respect to a direction in which the four piezoelectric-element rows are positioned side by side (hereinafter, referred to as the “side-by-side direction”). The leads are connected to respective contacts (e.g., segment terminals) positioned at end portions of the pressure chamber substrate in the side-by-side direction. The contacts are aligned in a row on each of the end portions of the pressure chamber substrate. The leads extending from the piezoelectric-element rows extend outwardly toward the respective corresponding contacts disposed on either of the end portions in the side-by-side direction. In the pressure chamber substrate, a wiring member (e.g., a tape carrier package (“TCP”)) is joined to each of the end portions on which the contacts are located. In each of the end portions, the wiring member and the contacts are electrically connected to each other.